


The Mistake

by InkedFoxtrot



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Cat Ears, F/F, Female My Unit | Byleth, Fire Emblem: Three Houses Black Eagles Route, Fluff and Humor, Not Beta Read, general silliness, i ask why not, you ask why
Language: English
Status: In-Progress
Published: 2020-02-19
Updated: 2020-02-19
Packaged: 2021-02-28 01:53:32
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,481
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/22805845
Author URL: https://archiveofourown.org/users/InkedFoxtrot/pseuds/InkedFoxtrot
Summary: It was a mistake. It was a shocking, unforeseeable and absolutely adorable mistake.Or:Byleth has cat ears for about a week.
Relationships: Edelgard von Hresvelg/My Unit | Byleth
Comments: 8
Kudos: 191





	The Mistake

**Author's Note:**

> My whole thought process for this two-chapter fic was basically: Edelgard like cats and Edelgard like Byleth, so why not both? That said, I haven't touched the game in a couple months, and I haven't written anything in a number of years, so I might be a bit rusty on both counts. Apologies ahead of time.
> 
> Also, I made Lysithea a Black Eagle in this story because I figured if it was going to be centered around Crest experimentation/removal, then she should definitely be a part of it.
> 
> In any case, I hope you enjoy this silly, little fic!

It was a mistake. It was a shocking, unforeseeable and absolutely adorable mistake. Edelgard von Hresvelg could only stare in stunned silence at the changes that had suddenly befallen her former professor.

When Byleth had stepped out of Hanneman’s old office, she looked almost exactly the same as when she had entered, except now her hair and eyes had returned to their previous teal color and she had _cat ears_? Linhardt and Lysithea soon followed Byleth out of the room and were explaining something to her, but their words didn’t reach Edelgard as all of the Emperor’s attention was solely focused on those two small, fuzzy ears resting on top of the teacher’s head.

Then suddenly, _wonderfully_ , one of them twitched.

It took all of Edelgard’s famed control not to let an unbecoming squee escape past her lips.

“... hanging open.”

Finally, words penetrated Edelgard’s mind and grounded her back into the here and now. She quite suddenly found herself on the receiving end of three sets of curious eyes and she made a conscious effort to collect herself. Not that it helped much, as her mind was still racing with numerous unanswered questions. “I’m sorry, Linhardt. What were you saying?”

“I said, your mouth is hanging open,” Linhardt replied flatly.

Edelgard couldn’t fight the light flush that suddenly tinted her cheeks and she lightly coughed into a gloved hand in a vain attempt to hide it. “I apologize. I was… distracted,” she finished, violet eyes darting back to the cat ears for a split second before meeting Linhardt’s gaze.

Her colleague merely shrugged. “That’s understandable. The professor does have cat ears now,” Linhardt replied in his usual blunt manner, but before Edelgard could question his blasé attitude to the _obviously_ abnormal situation (how was everyone else so calm! she was barely keeping herself together as it is!), another voice chimed in.

“Don’t worry, Edelgard! We’ll fix the professor as soon as we can!” Lysithea chirped, eyes full of determination while clutching a few well-worn tomes about Crests close to her body. The young mage’s confidence quickly faltered though, and she sheepishly looked to the side. “It’s my fault she ended up this way, after all.”

Byleth shook her head and managed to give Lysithea a small, comforting smile through her usual stoicism. “It’s alright. I volunteered, remember? I’d rather this happen to me than anyone else.”

It was true; once the strategist had learned of Linhardt and Lysithea’s Crest-removal studies taking place on Edelgard’s behest, Byleth had volunteered to be the guinea pig to Linhardt’s tests. At first the Emperor had vehemently refused, stating that any experimentation (Edelgard’s expression had grown sour at that word) could wait until after they had won the war. It wasn’t until Byleth had reminded Edelgard of Lysithea’s ‘limited time for such studies,’ as she had delicately put it, that Edelgard finally acquiesced.

Lysithea, however, still looked guilty. “That might be so, but I still want to apologize. It’s all because I mistranslated some runes before we recited the spells.”

“And _that’s_ because we haven’t had enough sleep,” Linhardt added, seemingly punctuating his words with a well-timed yawn. Seeing Edelgard’s pointed look, the scholar quickly held up his hand and explained. “I know you think I’m just trying to find an excuse to go take a nap, and while that’s often true, I would like to point out that we’ve been in the library for three days straight.”

Looking over to the youngest member of the group, Edelgard noted how dark the circles under Lysithea’s eyes had grown. The Emperor faintly recalled Hubert informing her of the pair’s frequent all-nighters in the library during the past month, burning candlelight until dawn broke through the windows. She relented with a small sigh, now more worried about their health than anything. “Please get some well-earned rest, you two. You can continue in a couple day’s time.”

“Will do, Your Majesty,” Linhardt responded in that sincere-sarcastic way that only he seemed to be able to pull off. As the two mages made their way past, Edgelard quickly called out to Lysithea before she disappeared from view around the corner.

“One last question: would either of you happen to have any idea on how long it will take to fix… these?” Edelgard made a vague gesture in the direction of Byleth’s newest additions. She didn’t know if she was quite ready to address the issue directly.

Another flash of guilt crossed Lysithea’s tired eyes. “I don’t know. It took us weeks to get this far, and depending on how much needs to be amended, it could take as little as a couple days, or as much as a few months.” _Months!_ “We don’t even know the entirety of the effects the current spells have.”

“I see.” That wasn’t quite what Edelgard wanted to hear, but it was now just another item to be added to a long list of things that needed to be taken care of. “Thank you Lysithea, and have a good evening.” The young mage nodded and disappeared down the stairs, leaving just Edelgard and Byleth standing alone in the monastery's long hallway.

A couple beats passed and Edelgard shifted awkwardly under Byleth’s gaze, her mind scrambling for words to fill the sudden silence. She asked the first thing to come to mind, “Do they hurt?” She internally reprimanded herself for asking such a silly question. Of course they don’t hurt, or Byleth would have given some indication that they did. Or wait, would she? This _was_ the notoriously-hard-to-read professor they were talking about...

Byleth shook her head, messy blue hair shifting with the gesture. “No. To be honest, I barely even notice them.”

“Oh. Good.” Edelgard heard herself respond lamely. Her violet eyes stole a few more curious looks before darting away while more and more questions filled her mind. However, there was one scandalous question she dared not ask, no matter how tempting it was. Her hand shifted restlessly at the thought, hoping the professor wouldn’t notice.

But of course Byleth noticed. “Do you want to touch them?”

Edelgard started. “I, How did...!?” Her face then flushed a light pink when she realized. “Was I that obvious?”

Byleth’s mouth briefly twitched into a smirk. “A little.”

The Emperor furrowed her brows at the tease, unable to stop the heat from growing on her cheeks. She stood up straighter in an attempt to regain some of her composure. “Would you allow me to t-touch them, my teacher?” Curse that treacherous stammer!

A hint of what Edelgard could only describe as amusement glinted past the professor’s eyes. “I did offer.”

“I-Indeed, you did.” Based on the warmth, Edelgard assumed her face was almost as red as her garb at this point, and thanked the Flames that it was nighttime, with the darkness pouring in from outside shielding most of her blush from her teacher’s astute gaze. Only Byleth could knock her so off-kilter. “Then I shall take you up on that offer.”

Mercifully, the former mercenary didn’t utter any more teasing words and simply lowered her head for easier access.

Edelgard removed her right gauntlet and slowly extended her hand to one of the pointy ears, willing herself to steady its shaking. She didn’t quite know what to expect, but when she gently grasped the ear, she let out a quiet gasp. _It’s so soft!_ She started to lightly rub it, feeling the fine, blue furs and delighting in the sensation. It reminded her so much of the cats in the colony around Garreg Mach Monastery! After a minute or so, she felt Byleth subtly lean her head into the rubs, eyes closing in content, and it was a few more minutes still when she heard a deep rumbling noise sound from Byleth’s throat.

“Professor?” Edelgard attempted to move her hand away, but Byleth lightly butted it back against her head, seemingly searching for more. “Professor, please,” she lightly chided, but more amused than anything. “It’s late and we should both head to bed.” She fully pulled her hand back to her side and only then did Byleth seem to awaken from whatever trance she was in.

Byleth tried to blink the grogginess away and when that failed, she reached up to rub one of her eyes. “I’m sorry, Edelgard. What did you say?” An ear flicked, as if still searching for the warmth of Edelgard’s hand.

“I said it’s late and we should both head off to bed,” the other repeated warmly, enjoying the adorable sight of a drowsy Byleth.

“Oh, right. Bed.” Byleth gave the Emperor a quick flash of a smile. “Goodnight, Edelgard. See you tomorrow.”

“Goodnight, my teacher.” Edelgard watched as Byleth ambled off and out of sight toward her living quarters. She was about to follow suit when a worrying thought hit her:

  
Could the sounds Byleth made be qualified as _purring?_


End file.
